A conventional casing assembly generally includes a casing that defining a receiving space and that is formed with an entrance for access into the receiving space, and a lid fastened detachably on the casing via a fastening device to cover the entrance so as to deny access into the receiving space.
Referring to FIGS. 1 and 2, a conventional casing assembly 1 (such as a notebook computer) includes a casing 2 (an outer casing of the notebook computer), a lid 3 and a fastening device 10. The casing 2 defines a receiving space 2″ (a battery-receiving chamber), is formed with an entrance 4″ for access into the receiving space 2″. The lid 3 has two engaging tongues 5, and is disposed on the casing 2 to cover the entrance 4″ in such a manner that the engaging tongues 5 extends into the receiving space 2″ via two through hole 4 in the casing 2. The fastening device 10 is mounted within the casing 2, and includes two locking bars 6 (only one is shown in FIG. 2), two stationary seats 9 (only one is shown in FIG. 2) fixed on the casing 2 adjacent to two opposite sides of the entrance 4, and two urging members 8 (only one is shown in FIG. 2) disposed between an adjacent pair of the locking bar 6 and the stationary seat 9 for urging the respective locking bar 6 to abut against the respective engaging tongue 5 of the lid 3, thereby fastening the lid 3 detachably on the casing 2.
Each of the locking bars 6 and the tongues 5 is provided with an inclined surface 6″ to facilitate insertion of the respective tongue 5 into the receiving space 2″ via the respective through hole 4 during insertion of the lid 3 into the entrance 4″ or removal of the lid 3 from the entrance 4″. It is relatively difficult for the user to remove the lid 3 from the casing 2 when he wishes to replace the battery (not shown), since the lid 3 is generally flush with the outer surface of the casing 2. The user must use his fingernails to poke out the lid 3 from the entrance 4″ in the casing 2, thereby inconveniencing the user.